Question 46: Magnetism and Matter

Question

An electron with energy 0.1 keV moves at right angle to the earth's magnetic field of 1 $$	imes$$ 10
$$-$$4
Wbm
$$-$$2
. The frequency of revolution of the electron will be :
(Take mass of electron = 9.0 $$	imes$$ 10
$$-$$31
kg)

Accepted Answer

$$T = {{2\pi m} \over {Bq}}$$
$$\Rightarrow$$ Frequency $$f = {{Bq} \over {2\pi m}}$$
$$ = {{{{10}^{ - 4}} 	imes 1.6 	imes {{10}^{ - 19}}} \over {2\pi  	imes 9 	imes {{10}^{ - 31}}}}$$
$$ \simeq 2.8 	imes {10^6}$$ Hz

Answer

$$1.6 	imes 10^{5} \mathrm{~Hz}$$

Answer

$$5.6 	imes 10^{5} \mathrm{~Hz}$$

Answer

$$2.8 	imes 10^{6} \mathrm{~Hz}$$

Answer

$$1.8 	imes 10^{6} \mathrm{~Hz}$$

Magnetism and Matter

An electron with energy 0.1 keV moves at right angle to the earth's magnetic field of 1 $\times 10 -4 Wbm -2 . The frequency of revolution of the electron will be : (Take mass of electron = 9.0 \times 10 -$31 kg)

Choose the correct answer: